14U-FM1
CU14FM1
IMPORTANT SERVICE SAFETY PRECAUTION
(Continued)
BEFORE RETURNING THE RECEIVER" Connect the resistor connection to all exposed metal
parts having a return to the chassis (antenna, metal
(Fire & Shock Hazard)cabinet, screw heads, knobs and control shafts,
escutcheon, etc.) and measure the AC voltage drop
Before returning the receiver to the user, perform
across the resistor.
the following safety checks.
AII checks must be repeated with the AC line cord
1. Inspect all lead dress to make certain that leads areplug connection reversed. (If necessary, a non-
not pinched or that hardware is not lodged betweenpolarized adapter plug must be used only for the
the chassis and other metal parts in the receivpurerpose of completing these chec.k.)
2. Inspect all protective devices such as non-metallicAny current measured must not exceed 0.5 milliamp.
control knobs, insulating materials, cabinet bacAny measurements not within the limits outlinedks,
adjustment and compartment covers or shieldsabo,ve indicate of a potential shock hazard and
isolation resistor-capacity networks, mechanicalcorrective action must be taken before returning the
insulators, etc.instrument to the customer.
3. To be sure that no shock hazard exists, check for
leakage current in the following manner.
" Plug the AC cord directly into a 120 volt AC outlet,
(Do not use an isolation transformer for this test).
" Using two clip leads, connect a 1.5k ohm, 10 watt
resistor paralleled b?yF capacitor in ser a 0.15ies with
all exposed metal cabinet parts and a known earth
ground, such as electrical conduit or electrical ground
connected to earth ground.
" Use an AC voltmeter having with 5000 ohm per volt,1.5k ohm
or higher, sensitivity to measure the AC voltage drop10W
across the resistor.
0.15 F
TEST PROBE
TO EXPOSED
CONNECT TO
METAL PARTS
KNOWN EARTH
GROUND
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SAFETY NOTICE
Many electrical and mechanical parts in teleFor continued protection, replacement parvisionts must be
receivers have special safety-related characteridentical to those used in the oristics.iginal circuit. The use of
These characteristics are often not evident from visualsubstitute replacement parts which do not have the same
inspection, nor can protection afforded by them besafety characteristics as the factory recommended
necessarily increased by using replacement componentsreplacement parts shown in this service manual, may
rated for higher voltage, wattage, etc.create shock, fire, X-radiation or other hazards.
Replacement parts which have these special safety
characteristics are identified in this manual; electrical
components having such features are identified ba"y "
and shaded areas in the Replacement Parts Lists and
Schematic Diagrams.
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